// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <stdint.h>

#include "build/build_config.h"
#include "media/base/simd/convert_rgb_to_yuv.h"

namespace media {

static int clip_byte(int x)
{
    if (x > 255)
        return 255;
    else if (x < 0)
        return 0;
    else
        return x;
}

void ConvertRGB32ToYUV_C(const uint8_t* rgbframe,
    uint8_t* yplane,
    uint8_t* uplane,
    uint8_t* vplane,
    int width,
    int height,
    int rgbstride,
    int ystride,
    int uvstride)
{
#if defined(OS_ANDROID)
    const int r = 0;
    const int g = 1;
    const int b = 2;
#else
    const int r = 2;
    const int g = 1;
    const int b = 0;
#endif

    for (int i = 0; i < height; ++i) {
        for (int j = 0; j < width; ++j) {
            // Since the input pixel format is RGB32, there are 4 bytes per pixel.
            const uint8_t* pixel = rgbframe + 4 * j;
            yplane[j] = clip_byte(((pixel[r] * 66 + pixel[g] * 129 + pixel[b] * 25 + 128) >> 8) + 16);
            if (i % 2 == 0 && j % 2 == 0) {
                uplane[j / 2] = clip_byte(((pixel[r] * -38 + pixel[g] * -74 + pixel[b] * 112 + 128) >> 8) + 128);
                vplane[j / 2] = clip_byte(((pixel[r] * 112 + pixel[g] * -94 + pixel[b] * -18 + 128) >> 8) + 128);
            }
        }
        rgbframe += rgbstride;
        yplane += ystride;
        if (i % 2 == 0) {
            uplane += uvstride;
            vplane += uvstride;
        }
    }
}

void ConvertRGB24ToYUV_C(const uint8_t* rgbframe,
    uint8_t* yplane,
    uint8_t* uplane,
    uint8_t* vplane,
    int width,
    int height,
    int rgbstride,
    int ystride,
    int uvstride)
{
    for (int i = 0; i < height; ++i) {
        for (int j = 0; j < width; ++j) {
            // Since the input pixel format is RGB24, there are 3 bytes per pixel.
            const uint8_t* pixel = rgbframe + 3 * j;
            yplane[j] = clip_byte(((pixel[2] * 66 + pixel[1] * 129 + pixel[0] * 25 + 128) >> 8) + 16);
            if (i % 2 == 0 && j % 2 == 0) {
                uplane[j / 2] = clip_byte(((pixel[2] * -38 + pixel[1] * -74 + pixel[0] * 112 + 128) >> 8) + 128);
                vplane[j / 2] = clip_byte(((pixel[2] * 112 + pixel[1] * -94 + pixel[0] * -18 + 128) >> 8) + 128);
            }
        }

        rgbframe += rgbstride;
        yplane += ystride;
        if (i % 2 == 0) {
            uplane += uvstride;
            vplane += uvstride;
        }
    }
}

} // namespace media
